Random numbers generator issue

[LW]

Hello. Recently I've found one oddity about Pelles C random numbers generator. Here's the test code:

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#include <stdio.h>
#include <stdlib.h>
#include <time.h>

int main(void)
{
       int i;
srand(time(NULL));

for (i = 0; i < 10; ++i)
printf("%u\n", rand() % 2);

return 0;
}

Besides Pelles C, I tried it on MSVS 2008, MinGW 4.4.0, Borland 5.5 cmd line tools and Tiny C compiler.

What I noticed is that Pelles C, unlike other compilers, tends to generate an output of all 1's with a frightening frequency. So I was unable to make it produce a valid 50/50 chance this way, and was forced to use (rand() % 100) < 50 instead. I personally count it as a significant bug.